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	Action (physics) - Wikipedia, the free encyclopedia
		In physics, the action is an integral quantity that is used to determine the evolution of a physical system between two defined states using the calculus of variations.
		The action is usually an integral over time, but may be integrated over spatial variables as well (for action pertaining to fields); in still other cases, the action is integrated along the path followed by the physical system.
		The action corresponding to the various paths is used to calculate the path integral, that gives the probability amplitudes of the various outcomes.
	en.wikipedia.org /wiki/Action_(physics) (1697 words)

	[No title]
		In essence, the precautionary principle provides a rationale for taking action against a practice or substance in the absence of scientific certainty rather than continuing the suspect practic e while it is under study, or without study.
		More science is critical to precautionary action, to monitor and measure sources and exposure, to uncover possible new sources of exposure, to research alternatives to chlorine, and to m ake sure that these alternatives do not pose serious problems of their own.
		The precautionary principle shall be applied when there are reasonable grounds for concern that a procedure or devel o pment may contribute to the degradation of the air, land and water of the Commonwealth.
	www.sehn.org /rtfdocs/handbook-rtf.rtf (11166 words)

	THE PRECAUTIONARY PRINCIPLE IN ACTION A HANDBOOK First Edition Written for the Science and Environmental Health Network ...
		An underlying theme of the principle is that decision-making in the face of extreme uncertainty and ignorance is a matter of policy and political considerations.
		The precautionary principle shall be applied when there are reasonable grounds for concern that a procedure or development may contribute to the degradation of the air, land and water of the Commonwealth.
		Community policy on the environment...shall be based on the precautionary principle and on the principles that preventive actions should be taken, that environmental damage should as a priority be rectified at source and that the polluter should pay.
	www.mindfully.org /Precaution/Precaution-In-Action-Handbook.htm (10900 words)

	Edwin F. Taylor - Principle of Least Action
		The principle of least action has wide applicability in undergraduate physics education, from mechanics in introductory classes through electricity and magnetism, quantum mechanics, special and general relativity—and it provides a deep foundation for advanced subjects and current research.
		Heuristic derivations of the Euler-Maupertuis abbreviated action and the Hamilton action.
		Action is a minimum along a sufficiently short worldline in all potentials and along worldlines of any length in some potentials.
	www.eftaylor.com /leastaction.html (1070 words)

	Principles of Nature: the principle of least action
		In my view, Least Action is curiously more powerful as a concept than the concepts of energy it entails (potential and kinetic energy) and perhaps one day the principle of Least Action will be understood in simpler visual mathematical terms and patterns that do not require this 'qualification' mandated by Einstein's theory.
		Just as in least action, in which time is considered globally (all at once) with a bird's-eye perspective, so resonant scale structures arise through a multiple integrative interactive process in which past and future are equal players....
		They are the result of global action and interaction, the residue, the crystal lattice, the clumpy outworkings of universal connection.
	www.principlesofnature.net /principle_of_least_action.htm (956 words)

	Principle of Least Action (part 4)
		The uncertainty principle follows from the interplay between the absolute value of the wave function (which describes the density distribution of the particle) and its phase (which describes the time evolution of the particle).
		The least action principle could be regarded merely as a technique that allows one to incorporate all equations characterizing the theory in a single formula.
		It is natural to expect that it should be possible to derive the action integral uniquely from the first principles -- such as in the case of special relativity.
	physics.ucsd.edu /~epivovar/action4.xml (1344 words)

	The Physics Classroom
		According to Newton's third law, for every action force there is an equal (in size) and opposite (in direction) reaction force.
		The baseball forces the bat to the right (an action); the bat forces the ball to the left (the reaction).
		The action force is stated; determine the reaction force.
	www.physicsclassroom.com /Class/newtlaws/U2L4b.html (363 words)

	Nanotechnology: Precautionary Principle Analyzed (Site not responding. Last check: 2007-11-03)
		The Precautionary Principle is often invoked when dealing with situations that might be hazardous; however, the label "Precautionary Principle" is attached to at least two different ideas, which must be analyzed separately.
		This paper discusses two forms of the Precautionary Principle, which we will call the "strict form" and the "active form", and relates them to the purpose of the Center for Responsible Nanotechnology, and to CRN's policy recommendations.
		First, almost any action creates a certain amount of risk, and this is especially true of research that seeks to answer unsolved questions.
	www.crnano.org /precautionary.htm (1389 words)

	Wheeler and Back-Action
		I have explained my back-action principle for the post-quantum generation of experiential qualities in terms of Einstein's principle of relativity that there are no "absolute ethers" on any level of physical reality.
		Einstein then discusses how his "equivalence principle" between inertia and mass for an electrically neutral test particle in "free-float" geodesic motion does this and how the inhomogeneous distribution of mass-energy stress causes a variable curving away from the flat space-time of special relativity.
		Here you have the basic principle of "back-action" of the post-quantum theory, which is really Einstein's principle of relativity somewhat disguised, i.e.
	www.qedcorp.com /pcr/pcr/Endtime.html (1718 words)

	A Small Dose Of... Toxicology
		Take action to avoid the possibility of serious or irreversible environmental harm even when scientific knowledge is incomplete or inconclusive.
		The precautionary principle asserts that the burden of proof for potentially harmful actions by industry or government rests on the assurance of safety and that when there are threats of serious damage, scientific uncertainty must be resolved in favor of prevention.
		Examples of actions with unintended negative consequences include the addition of methyl tert-butyl ether to gasoline in the United States to decrease air pollution, the drilling of tube wells in Bangladesh to avoid surface water microbial contamination, and village wide parenteral antischistosomiasis therapy in Egypt.
	www.asmalldoseof.org /precautionary/index.php (3174 words)

	Untitled Document
		As was developed in previous installments of this series, Leibniz and Bernoulli determined the characteristic nature of that principle, by determining first, the changing physical effect of that principle in the infinitesimally small, and then, by inversion, the overall characteristic of the principle.
		Thus, the unseen physical principle’s effect in the visible domain is expressed by the characteristic of change the principle of least-action demands.
		It was Riemann’s genius to recognize, through this application of Dirichlet’s Principle, that the principle of least-action of a physical process could be understood completely by the relationship between the boundary conditions and the singularities, and that this relationship could be expressed uniquely by Riemann’s geometric concept of complex functions.
	www.wlym.com /antidummies/part58.html (4050 words)

	The Action Principles®
		Let the guidance of these Action Principles® lead you to write your goals, make your plans, list your to-dos and make today and every day special.
		As an Action Principles® Champion, you'll be the best that you can be because you can't conceive of living any other way.
		We are happy and excited for you, that from this defining moment, you have the opportunity to discover the power of the Action Principles® to change your life and through your life to inspire others.
	www.actionprinciples.com (837 words)

	outcome counting, the action principle, and GR
		QFT ==> action principle ==> GR The derivation of GR from QFT is more problematic than the derivation of Newtonian mechanics from standard QM, as pointed out by Physics Monkey in msg #12 in [4].
		QFT ==> action principle ==> GR Firstly, QM was created by quantizing Hamiltonian mechanics, so it is no surprise that the FPI approach, which is analogous to Schrodinger/Heisenberg mechanics (as proved by Feynman), yields the principle of stationary action.
		I understand that Feynman recovered the path action principle in the QM of particles, but I'm still confused where exactly the action principle appears in QFT, ie whether it is assumed or recovered (as you say) from something else...
	www.physicsforums.com /showthread.php?p=935779 (1900 words)

	Fermat's Principle -- from Eric Weisstein's World of Physics
		The original statement of Fermat's principle was, "The actual path between two points taken by a beam of light is the one which is traversed in the least time." Snell's law and the law of reflection follow directly from this statement.
		It may be reformulated slightly in terms of optical path length as "Light, in going between two points, traverses the route having the smallest optical path length." In its original form however, Fermat's principle is somewhat incomplete and even slightly in error.
		Its modern form is "A light ray, in going between two points, must traverse as optical path length which is stationary with respect to variations of the path." In this formulation, the paths may be maxima, minima, or saddle points.
	scienceworld.wolfram.com /physics/FermatsPrinciple.html (140 words)

	Write Your Own - Catholic Action Principles
		We need your experience, knowledge and insights to make the Action Principles truly representative of those universal values and codes of conduct to which we should all endeavor to promote through our example.
		Your Action Principle should be between 80 and 200 words.
		It is understood and agreed that all Action Principle submissions and all photo and drawing submissions are made voluntarily without compensation or attribution to the contributor and become the property of the nonprofit American Success Institute which retains all publication rights in all forms.
	www.catholicactionprinciples.com /write (209 words)

	Sarfatti's Abstract. (Site not responding. Last check: 2007-11-03)
		Quantum theory in the Bohm ontology requires violation of the action-reaction principle between the "pilot wave" and the "particle".
		The quantum action, in particular, is a critical point in the space of Feynman histories.
		All of these actions mutually influence each other in "two-way relations" via the principle of minimal coupling in which ordinary partial derivatives for the Bohm point and ordinary functional derivatives for the fields are replaced by covariant derivatives with the torsion-anholonomic connection.
	www.mindspring.com /~cerebroscopic/Sarfatti-a.html (343 words)

	CHOOSING ACTIONS BY SYMMETRY
		Since the action we want is supposed to be a property of the path, where it is and what it is doing at that place and moment, the action should include no reference to how we choose to divide the time into little pieces to talk about it.
		Therefore the action that is associated with the combined little pieces of path should also just be the sum of the action associated with each of the little pieces independently.
		If the dynamics are to be local as a consequence of the action principle, the action we select must be a sum of little pieces of the action over little pieces of the path.
	www.ph.utexas.edu /~gleeson/httb/section1_3_6_10.html (2644 words)

	The Action Variational Principle in Cosmology
		During the last decade, the action variational principle of Peebles has proven to be a very applicable tool in the study of the formation of large-scale structures in the immediate neighbourhood of the Milky Way.
		It provides us with the mean to recreate the orbits of the galaxies from epochs early in the history of the Universe until the present, which in turn opens for a closer study of a number of subjects concerning the evolution of the Universe.
		In practise, the use of the action variational principle is a question of numerical optimization, a side of the method which previously has not been considered in detail.
	trond.hjorteland.com /thesis/hoved.html (395 words)

	Principle of least action - Wikipedia, the free encyclopedia
		Credit for the formulation of the principle of least action is commonly given to Pierre Louis Maupertuis, who wrote about it in 1744
		Maupertuis' priority was disputed in 1751 by the mathematician Samuel König, who claimed that it had been invented by Gottfried Leibniz in 1707.
		applied the variational principle to the function L = T − V to obtain what are now called the Lagrangian equations of motion.
	en.wikipedia.org /wiki/Principle_of_least_action (1501 words)

	TakingPrecaution.org - The Precautionary Principle in Action
		Chapter one of the Environment Code is a statement mandating the adoption of the precautionary principle throughout the city and county of San Francisco.
		In the San Francisco Department of the Environment's White Paper on The Precautionary Principle, the City and County of San Francisco provide an analysis of the core components of the precautionary principle and how it has been incorporated into policy at the local, state and national level.
		The Resolution mandates a precautionary principle ordinance and an Environmentally Preferable Purchasing Program to be developed for the City of Berkeley within one year.
	www.takingprecaution.org /inact_bayarea.html (803 words)

	THE SYNERGY PRINCIPLE (Site not responding. Last check: 2007-11-03)
		Corrective action here refers to the kind of action that will rectify the processes of differentiation and integration, producing synergy.
		Synergic Inquiry (Tang, 1995; 1996) is a process-oriented action methodology that transforms consciousness at various human system levels such as individuals, relationships, groups, organizations, communities, and societies.
		In its process of inclusiveness and consciousness expansion, synergy is a spiritual action process that leads to acceleration of evolution of consciousness.
	www.newciv.org /ISSS_Primer/seminzi.html (1027 words)

	[No title]
		Leibniz and Bernoulli determined the characteristic nature of that principle, by first determining the changing physical effect of that principle in the infinitesimally small, and then, by inversion, the overall characteristic of the principle.
		Thus, the effect in the visible domain of the unseen physical principle, is expressed by the characteristic of change demanded by the principle of least-action.
		Instead, Gauss insisted that these phenomena, as in the case of the catenary, must be understood as a unified process, in which the local variations in the position of the plumb bob or compass needle were a function of the characteristic of the principle governing the phenomenon as a whole.
	www.schillerinstitute.org /fid_02-06/2004/044_riemann_dirichlet.html (3892 words)

	The Hamilton Principle for the extended GN Equations
		The Hamilton Principle for the extended GN Equations
		The three-dimensional Euler equations for a rotating stratified incompressible fluid in the Boussinesq approximation follow from an action principle, with
		) apply generally for all vertically averaged fluid action principles in the Eulerian description and do not depend on the specific form of the action.
	public.lanl.gov /balu/nonhydro/node13.html (572 words)

	The Action Principle
		Given these conditions, the problem of extrimizing the action means that we must find where its first derivative is equal to 0.
		Thus, the path that extremizes the action is exactly that which solves the Euler-Lagrange equation, which is the classical path.
		The action principle is more than just a formal device.
	www.nyu.edu /classes/tuckerman/mol.dyn/lectures/lecture_3/node1.html (461 words)

	THE MINIMUM ACTION PRINCIPLE OF NATURE (Site not responding. Last check: 2007-11-03)
		Not that it was mandated by experimentation but because there was no reason to suppose otherwise.
		Quantum Mechanics emerged as a theory by imposing this strange restriction that action has a minimum value and only multiples of this value are allowed by nature.
		Three phenomenons which buffled classical physicists have been readily settled with this minimum action assumption.
	www.tryagain.com /physics/minact.htm (78 words)

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	A Commonsense Framework for Operationalizing the Precautionary Principle (Site not responding. Last check: 2007-11-03)
		The Precautionary Principle is a commonsense, prevention-oriented, principle which instructs policy makers and other decision-makers to think before acting and act based on suspected rather than proven effects (in other words, act in the face of uncertainty).
		This scale of actions to take would reflect both the level of proof/certainty of the adverse outcome from the weight of evidence determination as well as the potential impacts should that outcome occur (certainty of a specific adverse effect would also need to be considered).
		Decisions to take action to limit the input of potentially hazardous substances (or hazardous activities) in the environment are often taken only in response to the scientific establishment of a causal association between a substance activity and a well-defined negative impact.
	www.johnsonfdn.org /conferences/precautionary/tick.html (9275 words)

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